This paper deals with characteristics of the illuminance and the shadow factor within a shadow affected by reflected light, in an infinite length room which has a ribbon-shaped light source and a column (a shadow caster) of infinite length. Calculations are done by Monte Carlo method which is widely used lately to predict the illuminance distribution of a room. First, Monte Carlo method for numerical calculations is presented to obtain the illuminance within a shadow. Next, some experiments are made under the same conditions as the calculations. And, the experimental results are compared with the calculated results. As there is not a large difference seen between them, it is confirmed that the above method is suitable. Finally, the characteristics of the illuminance and the shadow factor on the floor at the varied reflectances of the room surface and the shadow caster are obtained and examined.

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Axial distributions of radiation intensity from coupled parallel plate RF glow discharges with RF power fixed at 30W and RF frequency at 13.56MHz, were measured as a function of gas pressure for neon and argon. The spectral intensities for neon and argon in RF glow discharges were also measured at a fixed RF frequency of 13.56MHz as a function of RF power. Furthermore, the axial distributions of spectral intensity were investigated as functions of gas pressure, RF power, and RF frequency. The gas pressure was varied over the range from 0.1 to 10.0 Torr, the RF power from 10 to 50W, and the RF frequency from 2MHz to 13.56MHz. It was observed that the radiation intensity has a maximum value at a certain distance from the driven electrode and shifts towards the electrode with increasing gas pressure. The spectral intensities increase in proportional to RF powers. The dependence of spectral intensity on gas pressure was similar to those of radiation intensity. It was found that the ion sheath formed in front of the driven electrode increased as the RF frequency decreased and that the spectral intensity decreased with decreasing RF frequency. The optical and spectral characteristics of the RF discharges were qualitatively discussed.

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Reduction of discomfort glare from a lighting installation is one of important factors for comfortable lighting. In a practical room, there are several light sources located at various positions. If an occupant look around room, he will see the light sources in both central and peripheral vision. Therefore it is important to establish criteria of discomfort glare effect for two or more sources in both central and peripheral positions. For the discussion on the criteria, the difference of the glare effects between central and peripheral visions needs to be clarified. However, the experiments in former studies are not sufficient for this purpose. Authours conducted an experimental study of subjective appraisal regarding the comparison of glare sensation from the light sources in the central vision and peripheral vision. Authours compared glare of light source in the central vision with each light source in the peripheral vision of upper side, right side and lower side location.
The results are as follows:
(1) Both source positions have similar slope in the equal-glare curve showing the relationship between source and background luminance.
(2) As far as the glare effects from solid angle of a source, peripheral vision of right side and lower side source positions is similar to central vision, but peripheral vision of upper side source position is not similar.
(3) The results regarding the peripheral vision of upper side source position, show some similarities to the study by Hopkinson and Bodmann.

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This paper describes a new dichroic reflector based on a substrate of plastic film. The conventional substrates for spotlights are made of glass or aluminum, while injection-molded plastic substrates recently became available. Therefore, the three materials were compared; glass, aluminum, and plastics. As a result, plastic films statified heat-resistance, stability, and optical characteristics were considered applicable. Especially, dichroic reflector based on plastic film with a protective coating were even stabler. Based on this, an asymmetric plastic film reflector with a 12V-50W halogen-lamp was developed.

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A model for the analysis of a lead - peaked ballast characteristics is developed. The model is derived using the equivalent circuit method of magnetic circuit. The magnetic path is divided into nine parts, and are expressed by equivalent inductors respectively. Iron loss at each part is represented by an equivalent resistance. For a discharge load, the discharge voltage - current model is adopted. Using the developed model, input and output characteristics are calculated and compared with the measured values at no-load, short-circuit load and discharge load condition, respectively. The calculated results agree well with the measured results both in waveforms and effective values.

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An image processing system for providing original images for synthesizing multiplex holograms is developed. This system reconstructs 3D (three dimensional) surface rendering images, two surfaces rendering images and/or band selected Computed Tomography values’ projection images of internal organs and/or bones of a patient from a series of tomograms such as CT (Computed Tomography). Image processing includes interpolation, enhancement, extraction of diseased parts, selection of axis of projection, and compensation of distortions. This research note presents the features of this system, and the results of new type images with conventional images.

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